Floppy magnetic recording discs are flexible discs of polyester resin or the like having a magnetic layer on each side thereof on which information is recorded by a magnetic head. Floppy discs which have a diameter of 31/2 inches (8.9 cm) or less are known as micro-floppy discs. Generally, the micro-floppy disc is accommodated in a hard casing to form a cartridge. The micro-floppy disc comprises a thin circular magnetic recording medium having a hub at its center.
The cartridge generally includes a fabric liner on both inner surfaces of the casing. The liner is contacted with the recording surface of the disc to remove debris on the recording surface while the disc is rotated. The liner has a width at least equal to the width of the recording region of the disc, and is forced against the entire width of the recording surface by a lifter secured to the inner surface of the casing.
A prior art micro-floppy magnetic recording disc cartridge 10 is shown in FIG. 1. The cartridge 10 is comprised of two cartridge shells 12A and 20A which enclose a floppy magnetic recording disc 16. The shells 12A and 20A each have a fabric liner 14 and 18, respectively, on their inner surface which approximates the shape of the disc 16. A prior art lifter 22 is provided in the form of a separate sheet of material that is affixed to the inner surface of the shell 20A and angled to apply pressure on the fabric liner 18. That pressure causes the fabric to rub against the disc 16, thereby cleaning the disc when it is rotated in the cartridge 10. The amount of resistance provided by lifter 22 and fabric liners 14 and 18 against rotation of the floppy disc 16 may be regulated during manufacture by adjusting the degree to which the lifter is angled from shell 20A.